Until I (blindly) ran the latest batch of updates, my Windows 8.1 Pro machine happily shared out its files to all and sundry, and could browse other systems in the same way.

After I ran the updates, no more sharing for me. None of my other devices could see the shares on my Windows 8.1 machine, and vice-versa. I don't know which of the updates broke my system, but the chronology of events is pretty compelling; I didn't install anything else on my computer apart from those updates...

Attempts to turn on both Network Discovery and File And Printer Sharing both silently failed without any prompts, dialogs, or error messages. I also could not find any obvious entries in EventVwr which might correspond to my attempts to turn sharing back on.

The tool provided on that web page is simply a self-extracting RAR archive, which can be easily extracted to check the contents first: a bunch of .REG, .INF, and .TXT files which are used by the tool to set various Registry keys and Service properties.

Anyway, that tool did the trick. File sharing and browsing both work again under Windows 8.1.